To expand the existing hard disk
Navigate to System > Shutdown. Click Shutdown. On prompting for confirmation, click OK.
Bring up the Azure Portal, navigate to Disks > Settings.
Click on the existing disk name under OS Disk.
Click Size + performance on the left panel of the page.
Edit the Custom disk size value.
Click Save.
Power on the Analytics.
Login to the Analytics UI using the IPV4 address, username and password.
Navigate to the System > Status. Verify that the added storage is displayed in Available Disk Space on Install Partition.